presign s3 urls based on prefix

aws_list_and_sign.py

#!/usr/bin/env python3
import boto3
import argparse


def list_objects(bucket, prefix="", suffix=""):
    s3 = boto3.client("s3")
    paginator = s3.get_paginator("list_objects_v2")

    for page in paginator.paginate(Prefix=prefix, Bucket=bucket):
        try:
            contents = page["Contents"]
        except KeyError:
            return

        for obj in contents:
            key = obj["Key"]
            if key.endswith(suffix):
                yield obj


def create_presigned_url(bucket_name, key, expiration):
    # Generate a presigned URL for the S3 object
    s3_client = s3_client = boto3.client("s3")

    response = s3_client.generate_presigned_url(
        "get_object",
        Params={"Bucket": bucket_name, "Key": key},
        ExpiresIn=expiration,
    )

    # The response contains the presigned URL
    return response


if __name__ == "__main__":
    parser = argparse.ArgumentParser()
    parser.add_argument(
        "-u",
        "--unit",
        default="hour",
        choices=["second", "minute", "hour"],
        help="Choose a time unit",
    )

    parser.add_argument("-t", "--time", default=4, help="Specify length of time.")

    parser.add_argument(
        "--suffix", default="", help="Output only keys ending with suffix, ie .tif"
    )

    parser.add_argument("S3URL")

    unit_seconds = {
        "second": 1,
        "minute": 60,
        "hour": 3600,
    }

    args = parser.parse_args()

    proto, _, bucket, prefix = args.S3URL.split("/", 3)

    ttl = args.time * unit_seconds[args.unit]

    for obj in list_objects(bucket, prefix, args.suffix):
        response = create_presigned_url(bucket, obj["Key"], ttl)
        print(response)